In cable reel assemblies such as described herein, the cable which may be used for a power transmission line that must be strung across poles may be carried to a work site on the bed of a truck. The cable spool is carried by a support structure which includes a brake device that may be set to either lock the spool to prevent unwinding of the cable or to set a predetermined amount of drag when the cable is being strung.
In my prior Application Ser. No. 721,035, now abandoned, there was disclosed a reel support and brake system for high tension cable stringing comprising, in general, a pair of spaced upright columns terminating in generally U-shaped ends which support a shaft adapted to receive the cable reel for rotation therewith and to bridge the column U-shaped ends. A brake device supported adjacent to one of the columns has a coupling member facing the U-shaped end of the column. The reel support shaft has a mutually engageable coupling member at its end directed to the brake device. The coupling members provide quick connection by way of a rib and slot arrangement adapted to slidably mate when the support shaft is vertically placed over the U-shaped column ends. In operation clamping devices may be placed in abutting relationship to the cable reel for the purpose of preventing the cable reel from sliding axially in an undesirable manner.
As indicated, in high tension wire stringing, wire discharged from a cable reel, at a desired and controlled rate, is strung across utility poles. During stringing it is important that proper adjustment of drag is obtainable to avoid flapping of the high tension wire as it is being discharged from the cable reel. Flapping of the wire being put up can result in contact with existing wire and even breakage thereof, possibly causing great harm to persons and property.
In addition, a positive brake setting must be maintained while loading and unloading of the cable reel or spool when the wire thereon has been expired.
The brake device as disclosed in my prior application was essentially a disc brake which included spaced supporting members, a friction disc mounted on a shaft journalled to the supporting members and a pair of spaced brake clamping arms having brake shoe means at their ends facing the sides of the disc, with the arms being carried by a threaded shaft having a wheel at its outboard end and adapted to move the brake arms toward and away from another upon rotation of the wheel. Insofar as the function and operation of the brake was concerned, it did provide for quicker, easier and safer cable stringing by virtue of the tension and control capabilities in the adjusting wheel that enabled setting up drag on the reel and obtaining the desired amount of sag in the cable as well as a positive lock up with ease of change over without disturbing the braking mechanism. However, there still was required a high degree of skill and experience by the operator to achieve the desired tensioning and drag set up in adjusting the hand wheel and ascertaining when sufficient tightening has occurred for lock up without over tightening engagement between metal parts of the wheel driven shaft and brake arm which are then difficult to loosen.